Warning for mentions of death and some very vague other stuff.

"He's ten."

"Yes, is there a problem?" Professor Oak barely turns from his computer to watch her, clenching her hands together with such worry the kids can sense it across the lab, though they can't hear any words.

"He's ten," she repeats, hoping for him to just understand her problem with what he intends to do.

"So? Green is also ten, if you hadn't noticed. They can be trusted," Professor Oak simply murmured, continuing to sort things on the computer. Delia had a difficult time not shouting in rage at him for not seeing.

"It's not about trust! They barely know left from right, professor! How could you possibly think of giving them a creature unknown to them and send them off, alone, into Kanto? Mr Mime senses something awful happening this year, and so does every other psychic I've spoken to! I demand that you wait until my Red is at least fourteen!"

Professor Oak finally turned, his look morphing from wary to aggravated, clearly feeling her ideas were not worth his time.
"By law, he may be given a pokémon at ten, and with his talents, I have no desire to change what has been done for centuries. I'm sure you must understand how this trip is an essential part of their schooling, Delia, and by using it and measuring their success we can see how well they will do later in life. I personally believe Red could go a very long way." He peered over at Red with a fond expression, observing as he played with Mr Mime that Delia had brought with her, Green watching on with his arms crossed. Returning his gaze to the distressed woman, he glared, mirroring Green's crossed arms to get his point across. "He is plainly bored. If left alone, without this opportunity, he will most likely kill himself before he ever reaches fourteen due to the lack of mental and physical stimulation."

Delia could no longer hold her anger back, only just refraining from slapping the Professor across the face by the merest hint of restraint.
"I'd rather he killed himself than got mauled to death by some creature in the middle of a field! You and the law are so archaic; no one can see what we are putting these children through!" Unable to keep her composure any longer, she fled from the lab, hoping Red would have enough sense to not take the creature that she knew Professor Oak would still offer.

Kanto had used to be in line with the other nations in regards to age at which children first received pokémon - but were now lagging far behind, Johto and Hoenn now legally at fourteen and looking set to raise it again, Sinnoh at sixteen and Unova, far away, eighteen. There was a saying often bantered around the world when mentioning children in Kanto, or the lack of; everyone always said the 'children grow up fast in Kanto'.

It wasn't entirely true.

Children were forced to grow up fast in Kanto.

Because the ones who didn't died on the journey.

Red blinked at Professor Oak as, shortly after his mom had left, he made his ambling way over to the two boys, not together but sitting in close-ish proximity. Out the corner of his eye, he saw Green roll his eyes, but he sat forward anyway, eager for what was about to happen.

"Now that is sorted, children, I may get on with what I called you here for. He rummaged into his pocket, and pulled out several pokéballs, checking them all and replaced some until he was left with just two. The professor glanced up at Red, and, selecting one pokéball, began giving it to Red.

Green, however, had different ideas.

"Hey, how come he gets one first! I'm having that one!" He snatched the pokéball, and immediately released the pokémon inside, a small dog-looking creature, who peered at Blue suspiciously for a moment before scampering off to a different section of the lab, Green chasing it with some confusion. Professor Oak watched them for a moment, before turning back to Red.

"Sorry, but Green seems to have taken a liking to that pokémon. I have this one though..." He held the pokéball out to Red once more; he took it with some hesitance. Glancing towards the door, he wondered what his mom was having a problem with; she'd never said anything to him, always encouraging him to learn, looking at maps of Kanto and charts of known pokémon. As if nothing had ever been disputable about the fact he would receive a pokémon at ten.

He looked back at the pokéball, saw the Professor's eager face, and so pressed the button to release the pokémon within it, the old man stepping back to leave so room for the emerging creature.

A yellow thing stood there, affixing on him a glare, clearly unimpressed. Its jagged tail stuck out from behind it, looking like a lightning bolt, and- Red guessed it was electric. That was weird, since most starter pokémon were grass or water, followed up by fire, but some people had issues controlling fire attacks, so it was less prevalent now than it had been.

Red glanced once more towards the door, then, turning back to the creature that Oak had explained was a pikachu, nodded slightly.

Delia took enough time to take in that Professor Oak had indeed given her child a pokémon, before she could not hold Red's gaze any longer. She hadn't wanted to force her ideas on her child, aware that for Kanto, they were revolutionary, but she'd hoped he might not take the pokémon. There was little point keeping him here for much longer now, he would want to take it places and explore, buoyed by the confidence of having a pokémon to protect him.

She turns back to the television, speaks distractedly.
"All boys leave home someday, Red."

She doesn't expect more than a light hug before he leaves, and that is all she gets.

It is then she decides she cannot forgive Professor Oak, even if Red does survive his trip.

As time passes, he learns. He learns that adults will always underestimate him; he learns that there are many bad things in the world. He learns that his feelings towards Green are different to that of other friends he makes, although he doesn't have the courage to learn why. He learns plenty about pokémon and battling, fighting bad people and he learns about death the hard way. He learns about progress and lack of it, languishing days when the end of the route seems so far away, exciting days when he's chasing down a new pokémon he's never seen before, or battling Green. He learns about fear, standing up to this awful bunch of people with Giovanni at the head of it, seeing massive pokémon and being unsure if they are about to try to rip his throat out or fall asleep next to him. He learns to judge right and wrong for himself, he learns to move past bad times in his journey, he learns how to be strong.

And at the pinnacle of it, Green is collapsed at one end of the championship field and his name is chanted by thousands in the stadium, and he is pushed towards the Hall of Fame when all he wants is to pick Green up from the floor. At that point, he learns his true desires: a quiet life, solitude (he'd make an exception for Green). He doesn't need any Hall of Fame, he doesn't need anyone chanting his name, and above all, he realises that he's learnt what he's lost by going on his journey: the wonder he used to have about the world.

He thinks of a mountain he saw once or twice, the roof of the world, and when he goes, Green is the only one to receive a note.

There is an eerie silence in the house, he realises as he steps over the threshold of the unlocked door. The lights haven't been turned on, the evening sun barely lighting the room with its closed curtains, the only light spills from the television screen where a pokémon battle rages. Vaguely outlining a still silhouette, she looks as though she has not moved in five years, more.

Stepping closer, he notes how she looks almost exactly the same as back then, although he hasn't seen her. Her hair falls the same way around the same coloured eyes, set on the screen as a massive pokémon falls, the ground-shaking fall impacted nothing to the silence pervading the space around them.

Yet he knows she has changed. Lines are etched into her skin faintly, those eyes glazed, as though this battle has been reviewed numerous times.

It will have done, he knows, knowing exactly who had fought that battle.

"You killed him." Her voice, quiet and devoid of emotion, startled him. Her eyes do not shift from the projected image, of wild crowds and resigned trainers, no more than children. Only now does he see that.

"He's not dead."
But it's weak, he knows it. The silence whispers his betrayal, his consuming desire to see one child grow to greatness disregarding what she had tried to tell him, all those years ago.

"That doesn't matter." He's not here, living a normal life.

It pains him to think of just how wrong he was.
"Delia, I... made a mistake. I ought to have heeded your words. Yet I was so desperate for him to grow into his potential, I dismissed the truth, in front of me."

She merely stands up, turning the screen off and plunging the area into darkness, before strolling over to one of the windows, throwing the curtains apart to cast her eyes at the dying sun. The entire sky is filled with a deep scarlet.

"Another year with no words. I don't suppose he had the chance to learn to write letters, did he?" Her words, emotionless, are far crueller than any anger she might have mustered. "Thirty. No one sees it, do they?"

A moment passes before his eyes widen in shock, disbelief, the lack of thought before crushing now. She's only thirty.

In that moment, he decides to change things, atone for his mistakes while he is still alive to do so. While she is still alive to see him make them.

"I'll discuss the matter with the appropriate parties."

She remains silent, doesn't turn, and as he walks out, he hears her soundless answer.

Five years, fifteen years too late.

Because childhood was the one thing that could never be returned.

He is beyond caring. Blank eyes watch the snow fall gently around him, gradually covering up his failure. He curls around the rapidly fading spot of warmth, tries to preserve it, feels the static crackling over him, but it grows weaker with each minute. The cold embeds itself into his body, his mind, his soul as a creeping deathly force that he wants to remove him from the world.

He had been the best, but now he was the worst.

He is beyond numb. He can't do anything. Perhaps he ought to blindly run in search of help, but there is none. He is alone on the top of the mountain, isolated and no one would answer if he called out. There is no hope, no joy, nothing left to live for. No past, no future, only this horrifically timeless moment here, lingering until there is nothing left of him, surrounded by the frozen corpses of his own beloved pokémon, clinging on to the only one he had a chance to save. The mountain will become his tomb, memorial, and gravestone, all in one, no carved name like in Pokémon Tower to remember him by, the child who wasn't, the adult who couldn't.

"Red!"

Suddenly, salvation becomes possible.

They have done nothing more than sit in silence. Wrapped in bandages, the gravity of it slowly weighs him down, and he weeps silently, face in his hands as though he cannot stand the thought of seeing the world. He can't. Everything blurs to red eventually, he never thought he'd hate his own name quite as much as he does now, and all through the hours, Green sits there with him.

The sliver of colour through the dominating red is the only thing that keeps him there.

Hours, days, months later, a nurse enters, smiles weakly although he is not looking to see it. He only recalls fading warmth, the decreasing tingle of sparks shuddering over him, and the lack of hope.

Even though it is as close to good news as he would ever get, he sobs, the first sound in that indefinite timespan between that and this. Turning, he buries his face in Green's shoulder, allows out all the emotion, sorrow and anger like adults are not supposed to do.

But he is not an adult.

It feels like hours to him before Green's arms stretch around him, recovered from the shock, and allow him to fall into – finally – safe, peaceful sleep.

Years later, he sits on Green's windowsill, looking out onto the Viridian City of the past, eyes clouded with what was, what could have been, mind recalling a time when this city was the only place he was aiming for. A frail pikachu curls up contentedly in his lap, sparks faintly shimmering white in the dim light. The scar that almost took its life stretches from the base of one ear to just above its tail, slightly raised even despite the healing techniques used back then.

He doesn't smile. There are only a few things he has to smile about really, one of them asleep in front of him, another not yet here. There is a lot to not smile about. His orphan status, the ghosts that continue to haunt him, despite his visits to Pokémon Tower. The mountain that he never escaped. The grim smile of the child who he'd failed to, who'd lost in not nearly as destructive way as Red had done.

He tries to remember what it was like to be a child, to be free of responsibility.

Either his memories have completely faded, or there are none. But either way, he lets it slip out of his mind momentarily, as his eyes turn from the city to the doorway, a taller thinner spikier-haired Green stands, watching him with a loving yet resigned gaze.

He smiles.

Children grow up fast in Kanto.

At twenty, they are beyond adulthood too.

I was going to stop after Professor Oak admitted his mistake, but the prompt was Green/Red and I felt it was lacking in a conclusion somehow. Not overly convinced I managed it here, but hopefully it was what the OP wanted, and that everyone else reading enjoyed it.

I just wanted to note my background thoughts – in this world, any 'fainted' pokémon that fainted while not in a gym or stadium die. There is some kind of protection in certain areas, but this doesn't stretch to the entire region, hence death.
When Delia mentions letters, she means correspondence. Red can write, he just doesn't.
Anything else that confuses you/you want to ask, go ahead! I'll try to reply quickly. But most of all, I hope you liked it, even though I know it was quite weird.

By the way, this is a kink meme fill, simply for Green/Red - 'children grow up fast in Kanto'.